Heavy snowfall blanketed eastern Sweden on Wednesday, causing power outages, major delays in rail and road traffic and grounding most planes at Stockholm's main airport Arlanda, officials said.

Some 30 centimetres (12 inches) of snow were expected Wednesday in the Stockholm region, where the power company said some 6,000 customers were without electricity as temperatures hovered around minus four Celsius (25 Fahrenheit).

"We are currently experiencing lengthy delays in air travel to and from Stockholm's airports Arlanda and Bromma," airport operator Swedavia said on its website.

Swedavia's website was also experiencing problems, due to the large number of travellers trying to access information about their flights.

From 6:00 am (0500 GMT) until midday, only 13 of 100 scheduled flights were able to land at Arlanda. Other flights were cancelled or postponed until later in the day, when the heavy snowfall was expected to ease up.

Between 6:40 am and 12:30 pm, only one in five planes was able to take off, as the heavy winds and snowfall reduced visibility.

Arlanda closed one of its runways, and the other one quickly turned treacherously icy in the cold conditions.

"We remove the snow, and a plane lands, but five minutes later it's the same thing all over again," airport spokesman Klas Nilsson told news agency TT.

"So now we're not allowing anymore planes to land and are prioritising travellers who are at Arlanda who want to depart," he added.

Some 60,000 passengers were affected by the delays, he said.

Rail traffic in Stockholm and its vicinity was also affected.

Facebook users complained about delays of up to three hours.

Public railway company SJ said on its website there were "delays due to the weather," but gave no further details.

In the capital, car, bus and tram traffic moved slowly, though metro traffic was largely undisturbed. In much of Stockholm, bundled up parents could be seen pulling their small children to daycare or school on sleds.